Method for Producing a Road Surface, Preferably a concrete road surface, and road paver

ABSTRACT

In the production of road surfaces of asphalt and concrete ( 33 ), it has been necessary hitherto to use different road pavers, which requires additional complexity, in particular when a wearing course ( 32 ) of concrete ( 33 ) is to be applied to a base ( 31 ) of asphalt. The invention provides to produce road surfaces of concrete ( 33 ) with a road paver intended for the processing of asphalt in that suspended vibrating bodies ( 23 ) are used which are inserted at least partially into the concrete ( 33 ) to be compacted. As a result, a road surface of concrete ( 33 ) can be produced with a road paver intended for the laying of road surfaces of asphalt. A laying screed ( 17 ) of the road paver is preferably guided rigidly, that is to say non-height-adjustably.

STATEMENT OF RELATED APPLICATIONS

This application is based on and claims the benefit of German Patent Application No. 10 2009 038 007.8 having a filing date of 20 Aug. 2009, which is incorporated herein in its entirety by this reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates to a road paver having a drivable set of running gear and at least one smoothing device which is arranged behind the running gear as seen in the paving direction, and also compacting means for the road-building material, preferably concrete, in front of the smoothing device. Furthermore, the invention relates to a method for producing a road surface, preferably a concrete road surface, with a self-propelled road paver from which the road-building material is compacted with compacting means and then is smoothed by at least one smoothing device.

2. Prior Art

Road surfaces are produced from asphalt (blacktop) or concrete. Moreover, however, there are also road surfaces which consist partially of asphalt and concrete. It is customary in this respect to apply a wearing course of concrete to a base or at least a lower layer of asphalt. In the case of asphalt road surfaces, for example, the milled-off worn asphalt wearing course is replaced by a concrete wearing course.

The production of asphalt road surfaces is carried out with self-propelled road pavers which are also referred to in the specialist jargon as blacktop pavers. Road surfaces of concrete are produced with pavers specifically provided therefor. Consequently, different pavers are required for road surfaces of different materials. That is particularly complicated when a wearing course of concrete is to be applied to an asphalt base.

BRIEF SUMMARY OF THE INVENTION

The object on which the invention is based is to provide a method which makes it possible with a road paver for asphalt road surfaces also to produce concrete road surfaces, in particular concrete wearing courses. It is an additional object of the invention to provide a road paver for the production of asphalt road surfaces which can also be used to produce concrete road surfaces.

A road paver for achieving this object has a drivable set of running gear and at least one smoothing device which is arranged behind the running gear as seen in the paving direction, and also compacting means for the road-building material, preferably concrete, in front of the smoothing device, characterized in that the compacting means are designed as vibrating bodies which are inserted at least partially into the road-building material. Accordingly, it is provided to design the compacting means as vibrating bodies which are inserted at least partially into the road-building material. The vibrating bodies make it possible with a road paver intended for the production of asphalt road surfaces to produce concrete road surfaces in that, by contrast with the production of asphalt road surfaces, where pressure is exerted from above onto the asphalt road-building material, the concrete is compacted not by pressure, but by oscillations, by the vibrating bodies inserted at least partially into said concrete. Consequently, the road paver according to the invention meets an essential prerequisite which is required to produce concrete road surfaces.

It is preferably provided to arrange the vibrating bodies between the running gear of the road paver and the smoothing device thereof. This arrangement preferably takes place in a suspended manner, with the result that the vibrating bodies, owing to their vibrating or oscillating movements, can be inserted without pressure from above into the fresh concrete in order to compact the latter by means of oscillations or other preferably periodic movements.

A preferred development of the road paver provides to fasten the vibrating bodies in a suspended manner on preferably one carrier. The carrier can be one on which the smoothing device and/or other components of the road paver are also held. The suspended arrangement makes it possible for the vibrating body to “dig” into the fresh concrete to an intended depth by means of vibrating movements in order to produce the road surface. The suspended arrangement of the vibrating bodies can take place on slack cables or chains, with the result that they can move out laterally, that is to say do not have any guidance in the paving direction and transversely thereto. However, it is preferably provided to suspend the vibrating bodies in a guided manner, preferably on rigid or on substantially rigid rods or tubes or similar strands. This prevents the vibrating bodies from deflecting or moving together as a result of the road paver moving along in the paving direction. Furthermore, tubes for the guided suspension of the vibrating bodies on the carrier can preferably serve for the energy supply of the vibration or unbalance generator arranged inside the vibrating bodies. These can be electric, hydraulic or else pneumatic lines.

It is further provided to arrange the vibrating bodies in at least one row extending transversely to the paving direction. Preferably, the vibrating bodies of at least one row are suspended over the entire working width of the road paver in a distributed manner on the carrier. As a result, the fresh concrete can be compacted uniformly over the entire working width.

In order to adapt to different conditions, it is further provided to adjust the spacing of the vibrating bodies from one another in a stepped or stepless manner and alternatively or in addition to suspend the vibrating body carriers in a height-adjustable manner. By altering the spacing of the vibrating bodies it is possible to change their spacing with the change of working width of the smoothing device. The height adjustment has the result that the vibrating bodies are inserted to a greater or lesser degree, but optionally also completely, into the fresh concrete in order to produce the concrete road surface. Accordingly, the degree of compaction of the concrete can be influenced individually.

The invention further provides to arrange the vibrating bodies in front of and/or behind a transverse distribution device for the road-building material. If the vibrating bodies are arranged both in front of and behind the transverse distribution device, that takes place in two parallel rows, of which one in each case is situated in front of and behind the transverse distribution device. The vibrating bodies are then expediently suspended on a carrier on which the transverse distribution device is also situated.

A method for achieving the object mentioned at the outset is a method for producing a road surface, preferably a concrete road surface, with a self-propelled road paver from which the road-building material is compacted with compacting means and then is smoothed by at least one smoothing device, characterized in that the road-building material is compacted by vibration and in so doing the compacting means are inserted at least partially into the road-building material. In this method it is provided that the road-building material, preferably concrete, is compacted by vibration and in so doing the compacting means are inserted at least partially into the road-building material. As a result of the vibration it is possible with a road paver for asphalt road surfaces to effectively compact concrete for road surfaces to be produced therefrom. By inserting the compacting means into the concrete, the latter is caused by the compacting means to make vibrating movements, in particular oscillations. These periodic movements lead to an effective compaction of the concrete for a concrete road surface which is produced with a road paver for asphalt road surfaces.

A preferred development of the method provides that the smoothing device of the road paver is guided at the working height. By contrast with the usual floating operation of the smoothing device in the production of asphalt road surfaces, in which case the smoothing device bears with its own weight on the fresh road surface, the guiding of the smoothing device at the intended working height has the result that the smoothing device forms a virtually rigid unit with the remaining part of the road paver, in particular its drive, and consequently the smoothing device, together with at least part of the weight of the road paver, is supported on the freshly laid concrete road surface.

The smoothing device is preferably guided rigidly or fixed rigidly at the working height. The working height thus only changes if this is required as a result of an arched profile of the base of the road or a change of the layer thickness of the concrete road surface. Furthermore, it is preferably provided to guide the smoothing device with a height controller or regulator in that the rigid guidance of the smoothing device, which is preferably a laying screed, in particular a high-compaction laying screed, is maintained.

The compacting means are preferably driven in a permanently vibrating, preferably oscillating, manner, specifically independently of one another by in each case their own drive. According to a preferred embodiment of the invention, the frequency with which the compacting means are driven in a vibrating or oscillating manner can be varied, with the result that they can be adapted individually to the prevailing conditions.

BRIEF SUMMARY OF THE DRAWINGS

A preferred exemplary of the invention will be explained in more detail below with reference to the drawing, in which:

FIG. 1 shows a side view of a road paver.

FIG. 2 shows a rear part of the road paver of FIG. 1 on an enlarged scale.

FIG. 3 shows a plan view of a smoothing device and compacting means of the road paver.

FIG. 4 shows an enlarged detail IV from FIG. 3.

FIG. 5 shows a schematic plan view of the road paver.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 schematically shows a road paver 10 which is designed according to the invention in such a way that it serves not only for producing an asphalt road surface but is also suitable for producing a concrete road surface. The road paver 10 is also especially suitable for applying a concrete wearing course to an existing asphalt road surface whose worn wearing course has been removed, for example, by milling.

The road paver 10 has a set of running gear 11 which in the exemplary embodiment shown is designed as a tracked running gear. The running gear of the road paver 10 can, however, also be a wheeled running gear.

As seen in the paving direction 12, a well-like or trough-like reservoir 13 is arranged on the front of the road paver 10. The reservoir 13 serves to accommodate a supply of the material serving for the production of the road surface, namely an asphalt mixture if the road paver 10 is used to produce an asphalt road surface. By means of a conveying member, in particular a scraper conveyor 14 (FIG. 5), the asphalt mixture is transported from the reservoir 13 counter to the paving direction 12 to a rear end 14 of the road paver 10. However, to produce the concrete road surface or a concrete wearing course, the reservoir 13 is generally not used.

The road paver 10 has at the rear end 14, specifically behind the running gear 11, a distribution auger 16 which extends transversely to the paving direction 12 and serves to distribute the material for producing the road surface uniformly over the entire working width of the road paver 10. As seen in the paving direction 12, there is situated behind the distribution auger 16 a smoothing device which, in the case of the road paver 10 shown here, is a laying screed 17. The laying screed 17 and the distribution auger 16 are suspended on two carrying arms 18. The carrying arms 18 are mounted pivotably on the running gear 11 by the hydraulic cylinder 19 in order to move the laying screed 17 and the distribution auger 16 up and down. The laying screed 17 can be either non-variable in its width or variable in its width. Such a laying screed 17 allowing a variation of the working width of the road paver 10 is shown in the figures. This laying screed 17 has a central main screed 20 and two displacement screeds 21 which are movable on opposite sides of said main screed transversely to the paving direction 12.

In the case of the laying screed 17 shown here, vertical side plates 22 are provided at the outer, free ends of the displacement screeds 21, the longitudinal directions of which plates extend in the paving direction 12. The side plates 22 thus lie in parallel and vertical planes which extend in the paving direction 12.

The road paver shown here 10 has, in order to process concrete 33 to a concrete road surface or a concrete wearing course 32, a plurality of compacting means which are designed as vibrating bodies 23 according to the invention. The vibrating bodies 23 are preferably equally designed vibrating cylinders. The vibrating bodies 23 are arranged between the running gear 11 and the laying screed 17. This arrangement is such that all the vibrating bodies 23 are arranged in a suspended manner on a carrier 24 connected to the carrying arms 18. In the exemplary embodiment shown in FIG. 2, two parallel rows each having a plurality of vibrating bodies 23 and extending over the respective working width of the road paver 10 are suspended on the carrier 24 which can be moved up and down by the carrying arms 18. Here, one row having vibrating bodies 23 is situated between the running gear 11 and the distribution auger 16, while the second row having a plurality of vibrating bodies 23 is situated between the distribution auger 16 and the laying screed 17. The vibrating bodies 23 of this second (rear) row are also suspended on the carrier 24 which can be moved up and down by the carrying arms 18. However, it is also conceivable for the road paver 10 to have only one row of a plurality of vibrating bodies 23 which can be arranged both in front of and behind the distribution auger 16.

The carrier 24 has a rod 25 which extends transversely to the paving direction 12 and which, if appropriate, can also be of tubular design. Opposite ends of the rod 25 are telescopically extendable, with the result that the rod 25 can be adapted to the variable working width of the road paver 10, namely the respective width of the laying screed 17. In order to adapt to the working width of the road paver 10, the movable ends of the rod 25 are moved together or apart by suitable drives, in particular by hydraulic cylinders or racks.

Each vibrating body 23 is assigned a sleeve 26 which can be displaced on the rod 25. On the sleeve 26, the respective vibrating body 23 is connected to a column-like upper holding rod 27 or a holding tube. A vertical slot 28 is situated in the holding rod 27 of each vibrating body 23. Consequently, the height of the respective vibrating body 23 is adjustable, specifically in such a way that the vibrating body 23 is inserted to an intended extent into the concrete 33 in front of the laying screed 17. The spacing of the vibrating bodies 23 from one another is adjustable by displacing on the rod 25 the respective sleeve 26 connected to the holding rod 27. In the exemplary embodiment of FIG. 4, the spacing adjustment of the vibrating bodies 23 transversely to the paving direction 12 is effected in a stepped manner in that a row of a plurality of spaced-apart through holes 29 is provided in the rod 25 and the sleeve 26. By means of a screw plugged through a selected through hole 29, both the spacing of the vibrating bodies 23 from one another and the height of the vibrating bodies 23 can be fixed. Alternatively, it is also conceivable to provide a stepless adjustment of the spacing of the vibrating bodies 23 transversely to the paving direction 12 in that the sleeve 26 is fixed against lateral displacement by corresponding catches at the intended points on the rod 25.

The vibrating bodies 23 suspended on one or, if appropriate, also a plurality of rods 25 can, when not in use, for example when the road paver 10 is to be used for producing asphalt road surfaces, be swung up into the non-use position shown in dashed lines in FIG. 2. This can take place manually, but also by means of corresponding pivoting drives.

The cylindrical vibrating bodies 23 preferably designed as vibrating cylinders are provided on the inside with a vibration exciter which is formed for example by an unbalanced drive. The unbalanced drive or some other vibration generator is operated electrically by an electric motor arranged in the vibrating body 23 or hydraulically or pneumatically. The energy required for this purpose is supplied by the drive of the road paver 10. The vibrating movements of the vibrating bodies 23 are preferably directed radially to the longitudinal centre axis 30 of the vibrating body 23, specifically in any desired directions or all around. However, it is also conceivable, alternatively or additionally, to move the vibrating bodies 23 in a vibrating or oscillating manner in the direction of the longitudinal centre axis 30.

The method according to the invention will be explained in more detail below with reference to the above-described road paver 10:

According to the method according to the invention, the road paver 10 shown, which is usually used for producing asphalt road surfaces, is also used to produce road surfaces of concrete. FIG. 2 shows how, with the road paver 10, a wearing course 32 of concrete 33 is applied to any desired base 31, which can also be an asphalt surface with a milled-away wearing course.

According to the representation in FIG. 5, the concrete 33 is, for example, unloaded from a concrete mixer onto the base 31 on opposite longitudinal sides of the road paver 10, specifically as concrete heaps 34 on opposite sides of the road paver 10. By moving the road paver 10 in the paving direction 12, the concrete heaps 34 come into the area of influence of opposite outer ends of the distribution auger 16, with the result that the concrete 33 of the concrete heaps 34 is substantially uniformly distributed over the entire working width of the road paver 10 in front of the laying screed 17.

The supply of concrete 33 (FIG. 2) accumulating in front of the laying screed 17 is compacted by the vibrating bodies 23. Here, the vibrating bodies 23 are guided in a suspended manner below the carriers 24, specifically in such a way that they are held laterally by the holding rods 27, that is to say cannot substantially move—apart from the vibrating movements—in the paving direction 12 and in the direction transversely thereto. During compaction, the vibrating bodies 23 are inserted at least partially into the concrete 33. As a result, the concrete 33 in front of the laying screed 17 is excited to make vibrating or pulsating movements by the vibrating or oscillating movements of the vibrating body 23 and is thus compacted.

By changing the spacing of the vibrating bodies 23, their insertion depth into the concrete 33 and/or the oscillation frequency, the extent of compaction can be adapted to the type and the mixing ratio, in particular the consistency, of the concrete 23. The corresponding settings and adjustments are preferably effected by controllers and adjusting drives which can be influenced by the operator from the operator's station 35 of the road paver 10.

During the production of the wearing course 32 formed from the concrete 33, the laying screed 17 is not operated in the usual floating manner as in the production of road surfaces of asphalt, but is fixed in its height. Here, the laying screed 17 is preferably suspended rigidly on the carrying arms 18, just like the distribution auger 16 and the carriers 24 for the vibrating bodies 23. The carrying arms 18 too are not moved here. As a result, when producing the wearing course 32 formed from the concrete 33, the height of the laying screed 17 remains unchanged relative to the running gear 11. In this way, the laying screed 17 presses not only with its own weight, but also with the weight of the road paver 10, onto the concrete 33 in order to form the wearing course 32. Only if the thickness of the wearing course 32 is to be changed or the height profile of the base 31 requires it, does a controller raise or lower the laying screed 17 by pivoting the carrying arms 18 which can be actuated by the hydraulic cylinders 19. The laying screed 17 which is fixed in height or rigidly guided can, by means of the controller, which is preferably an automatic levelling device, be changed in its height and transverse inclination if required.

If it is intended for a road surface of asphalt to be produced with the road paver 10, it is easily convertible in that only the vibrating bodies 23 are pivoted up by rotating the sleeves 26 about the rod 25 into the position represented in dashed lines in FIG. 2. As a result, the vibrating bodies 23 are brought into a rest position for the laying of asphalt, for which purpose they are not required. Furthermore, the laying screed 17 is then operated in a floating manner. Conversely, the road paver 10 can be easily converted for the laying of concrete 33.

As a departure from the representation in FIG. 5, it is also conceivable to provide a V-shaped plate in front of the running gear 11 of the road paver 10, which plate, in the manner of a plough, cleaves the concrete heap deposited in front of the road paver 10 and guides the concrete 33 past on both sides next to the road paver 10. This produces, on opposite sides of the road paver 10, continuous strands of concrete 33 which are spread out behind the running gear 10 by the distribution auger 16 in a preferably uniform manner over the entire working width of the road paver 10 in front of the laying screed 17 and are compacted by the periodically oscillating vibrating bodies 23 which are inserted into the concrete 33.

A further alternative design of the road paver for implementing the above-described method is distinguished in that the laying screed 17 is replaced by a smoothing device having a rail extending transversely to the paving direction 12. The rail smoothes out the concrete 33 which is situated between the side plates 22 and compacted or precompacted by the vibrating bodies 23. The rail of the smoothing device is also guided non-height-adjustably by the road paver 10, namely is held rigidly behind the running gear 11 of the road paver 10 during the production of the wearing course 32, specifically preferably on the carrying arms 18.

LIST OF REFERENCE NUMBERS

-   10 Road paver -   11 Running gear -   12 Paving direction -   13 Reservoir -   14 Scraper conveyor -   15 Rear end -   16 Distribution auger -   17 Laying screed -   18 Carrying arm -   19 Hydraulic cylinder -   20 Main screed -   21 Displacement screed -   22 Side plate -   23 Vibrating body -   24 Carrier -   25 Rod -   26 Sleeve -   27 Holding rod -   28 Slot -   29 Through hole -   30 Longitudinal centre axis -   31 Base -   32 Wearing course -   33 Concrete -   34 Concrete heap -   35 Operator's station 

1. A road paver having a drivable set of running gear (11) and at least one smoothing device which is arranged behind the running gear (11) as seen in the paving direction (12), and also compacting means for the road-building material in front of the smoothing device, wherein the compacting means are vibrating bodies (23) which are inserted at least partially into the road-building material.
 2. The road paver according to claim 1, wherein the vibrating bodies (23) are arranged between the running gear (11) and the smoothing device.
 3. The road paver according to claim 1, wherein the vibrating bodies (23) are arranged in a suspended manner between the running gear (11) and the smoothing device.
 4. The road paver according to claim 1, wherein the vibrating bodies (23) are arranged in at least one row extending transversely to the paving direction (12).
 5. The road paver according to claim 1, wherein the vibrating bodies (23) are suspended in a guided manner on a carrier (24).
 6. The road paver according to claim 5, wherein the vibrating bodies (23) are suspended in at least one row on the carrier (24).
 7. The road paver according to claim 5, wherein the vibrating bodies (23) are suspended in a height-adjustable manner on the carrier (24).
 8. The road paver according to claim 1, wherein the spacing of the vibrating bodies (23) from one another is adjustable.
 9. The road paver according to claim 1, wherein the vibrating bodies (23) are arranged in front of a transverse distribution device for the road-building material.
 10. The road paver according to claim 1, wherein the vibrating bodies (23) are arranged behind a transverse distribution device.
 11. The road paver according to claim 1, wherein the vibrating bodies (23) are designed to compact concrete (33).
 12. The road paver according to claim 1, wherein the vibrating bodies (23) each have their own vibrating drive.
 13. The road paver according to claim 1, wherein the vibrating bodies (23) are vibrating cylinders.
 14. A method for producing a road surface with a self-propelled road paver (10) from which road-building material is compacted with compacting means and then is smoothed by at least one smoothing device, comprising compacting the road-building material by vibration and in so doing inserting the compacting means at least partially into the road-building material.
 15. The method according to claim 14, further comprising driving the compacting means in an oscillating manner.
 16. The method according to claim 14, wherein the road-building material is concrete, and further comprising compacting the concrete (33) for a concrete road surface by the compacting means.
 17. The method according to claim 14, wherein the compacting means used are vibrating bodies (23).
 18. The method according to claim 14, further comprising guiding the smoothing device at the working height.
 19. The method according to claim 14, wherein the smoothing device is guided by a height controller. 